Method and apparatus for continuous metal casting

ABSTRACT

Continuous casting apparatus for the manufacture of a strip of anodes includes upper and lower flexible belts having edge dams disposed between them. The edge dams are movable and are formed by a series of blocks which provide spaced recesses to permit the formation of integral lugs on the anodes. Alternatively or in addition the edge dams have spaced inwardly directed projections to provide for the formation of recesses in the edges of the anodes. The edge dams are constrained by guides to depart from the line of the cast strip at a shallow angle to enable ready withdrawal of the anodes.

United States Patent Garlick Jan. 14, 1975 [54] METHOD AND APPARATUS FOR3,036,348 5/1962 Hazelettetal 164/278 O NUOUS METAL CASTING 3,300,821l/1967 Nichols et al 164/278 3,776,679 12/1973 Hegler 425/326 R [76]Inventor: Thomas William Gal-lick, 4

Bloomsbury 9- London England Primary ExaminerR. Spencer Annear 22 Filed;Man 8, 973 Attorney, Agent, or Firm-Brumbaugh, Graves,

Donohue & Raymond [21] Appl. No.: 339,362

[57] ABSTRACT [30] Foreign Application Priority Data Continuous castingapparatus for the manufacture of a Mar. 10, 1972 Great Britain 11334/72Strip of anodes includes pp and lower flexible belts Mar. 30, 1972 GreatBritain 15104/72 having edge dams disposed between them- The edge damsare movable and are formed by a series of 52 U.S. c1. 164/87, 164/278blocks which Provide Spaced recesses to Permit the [51] 1nt.Cl B22d11/06 formation of integral lugs on the anodes. Alternatively [58] Fieldof Search 164/82, 87, 278, 279 or in addition the edge dams have spacedinwardly rected projections to provide for the formation of re- [5References Cited cesses in the edges of the anodes. The edge dams areUNITED STATES PATENTS constrained by guides to depart from the line ofthe cast strip at a shallow angle to enable ready withdrawal of theanodes.

21 Claims, 18 Drawing Figures PATENTED JAN 1 M975 SHEET 1 0F 7 ,31oB-1'; 1 FI FIG. 5.

3,860,057 SHEET 6 BF 7 T Ill I1... I

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m w .i in 1 A 1 1 1.----m 5- 3 2-2 i ug i iii PATENTED JAN 4l975 METHODAND APPARATUS FOR CONTINUOUS METAL CASTING BACKGROUND OF THE INVENTIONIt has been proposed, for example in U.S. Pat. No. 3,036,348, to providecasting apparatus which produces a continuous strip of metal which issubsequently cut into a number of more or less identical pieces whichare normally provided with hangers to enable them to be handled by theappropriate machinery and suspendedin electrolytic cells.

One disadvantage of such an arrangement is that the hangers, once theanodes have been used, have to be returned to the casting apparatus foruse with new anodes. This involves the use of labour and machinery whichcould be more economically used elsewhere in the process. I

SUMMARY OF THE INVENTION According to one aspect of the presentinvention, molten metal casting apparatus comprises an endlesssupporting belt and movable edge dams defining between them and with thebelt a casting region for a continuously cast strip, the edge dams eachhaving a laterally shouldered section to enable the integral formationof a supporting shoulder on each side of the cast strip. The laterallyshouldered section may comprise a recess in the edge dam in order toform integral supporting lugs on the cast strip. Alternatively, thelaterally shouldered section may comprise a projection from theremainder of the face of the dam in order to form a recess in the edgeof the cast strip.

If desired, the face of the dam may have a recess therein adjacent aprojection in order to form a laterally projecting lug on the cast stripand an adjacent inwardly extending recess.

In order to maintain the advancement of the dams in correctly phasedrelationship, synchronisation means may be included which is adapted toco-operate with means, such as slots on each edge dam.

The edge dams preferably have a length which is longer than that of thesupporting belt so that they may separate from the belt over a part oftheir path. For example, according to a specific aspect of the presentinvention, apparatus for the continuous casting of metal strip comprisesat least one substantially flat supporting belt which is movable, in acasting region, in a planar path, a pair of horizontally spaced edgedams positioned immediately above the supporting belt and definingtherewith a casting channel, the dams being movable in the samedirection and at substantially the same speed as the supporting belt,the edge dams having opposed faces which at least at one region of eachhas a laterally shouldered section to enable the internal formation of asupporting shoulder on each side of the cast metal strip, means forsupporting the cast strip as it leaves the casting region, and means forconstraining the edge dams, beyond the casting region, to follow a pathwhich is inclined to the cast strip at a shallow angle.

For example, the cast strip as it leaves the casting region may follow asubstantially horizontal path and the edge dams may be constrained tofollow a downward path, for example at an angle at inclination withrespect to the cast strip of between 2 and 10 and specifically 5.

Alternatively the cast strip as it leaves the casting region follows adownwardly inclined path and the means for constraining the edge damscauses the edge dams to move upwardly beyond the casting region.

In order further to assist in the removal of the lugs, the trailing endwalls of the recesses by which they are formed may be inclined upwardlyand rearwardly ofthe recess. This inclination may be of the order of 1020 but about 14 is preferred. Similarly, a taper may be made on theleading end wall of each recess. Such a taper may be of the order of afew degrees, for example 5.

The invention also relates to a method of continuously casting a metalstrip comprising forming a casting region between an endless supportingbelt and movable edge dams which have laterally shouldered sections andintroducing molten metal into the casting region to form a cast striphaving integral supporting shoulders defined by the laterally shoulderedsections.

BRIEF DESCRIPTION OF THE DRAWINGS AND THE PREFERRED EMBODIMENTS FIG. 1diagrammatically illustrates several continuously cast anodes and at thesame time shows one method of suspending an individual anode afterseverance;

FIGS. 2 to 6 each illustrate a different form of anode which can bemanufactured in accordance with the present invention;

FIG. 7 is a diagrammatic side elevation of one form of casting apparatusaccording to the present invention; FIG. 8 is a plan view of theapparatus shown in FIG.

FIG. 9 is an end elevation as seen in the direction of the arrow A inFIG. 8;

FIG. 10 is a diagrammatic cross section on an enlarged scale of certainparts of the apparatus of FIGS. 7 to 10;

FIG. 11 is a cross section taken on the line 1lll of FIG. 10;

FIG. 12 is a plan view of part of an edge dam which is suitable forforming the anode shown in FIG. 2;

FIG. 13 is a side elevation of the edge dam of FIG. 12;

FIG. 14 is a plan view of part of an alternative form of edge damsuitable for forming the type of anode shown in FIG. 4;

FIG. 15 is a sectional elevation on the line I5l5 of FIG. 14;

FIG. 16 is a plan view of part of a modified edge dam;

FIG. 17 is a section on the line l7l7 of FIG. 16; and

FIG. 18 is a view, similar to FIG. 7, of an alternative embodiment.

Referring firstly to FIG. 1 this shows an anode 10 formed by acontinuous casting process in a manner to be described. Adjacent anodes10a and 10b are formed during the casting process but are sheared offwhen solidified, the anodes 10a and 10b having been shown in FIG. 1simply to give an indication of the general method of manufacture.integrally formed with the body of the anode 10 are a pair of lugs 11,one on each side, by means of which the anode 10 can be suspended onsupports 12, which include contact bars 13, during the time the anode ispositioned within a cell.

If desired, in order to make it unnecessary for the projection of thelugs 11 to be sufficient to enable lifting hooks to be positioned onthem between the contact bars and the edge of the anode, and to enablethe anode to be lifted into and removed from the cell, it can beprovided with holes 14 to accommodate arms of a lifting device.

The alternative form of anode shown in FIG. 2 is generally similar tothat of FIG. 1 and like parts bear. like reference numerals. Immediatelyadjacent the lugs 11 the anode is provided with recesses which arespaced from the supports 12 so that arms of a lifting device can beinserted under the lugs ll in the recesses 15 so avoiding. the necessityof the separate step of making holes 14 in the anode as described withreference to FIG. 1.

FIG. 3 shows a slightly modified anode indicating that it is notessential for the lugs 11 and recesses 15 to be symmetrically disposed.

The anode shown in FIG. 4 also has a main body part 10 but has nolateral lugs. Recesses 16 are provided one on each side and in this casethe anodes are suspended in cells by hanger bars 20 having arms 21 whichengage in the recesses 16. A specific form of apparatus will bedescribed for casting the type of anode shown in FIG. 4 when referringto FIGS. 14 and 15, and although this anode has the disadvantage that aseparate hanger is needed, the fact that the recesses 16 are castintegrally with the body of the anode means that no additionalmanufacturing step has to be performed after casting and shearing and inaddition the thickness of the anodes is reasonably constant even in theregion of the recesses.

In all the embodiments so far described the shear lines 60 betweenadjacent anodes are straight and at right angles to the direction ofcasting. FIG. 6 illustrates an alternative arrangement, however, inwhich the shear line takes an alternative form 60a.

Referring now to the diagrammatic illustrations in FIGS. 7, 8 and 9,these show a casting apparatus having an upper flexible casting belt 31and a lower flexible casting belt 32. Both belts are continuous andmovable in the direction of the arrows shown. Each belt is supported bya carriage assembly including four rollers about which the belts move.The rollers for the belt 31 are indicated by the reference numerals 33ato 33d and those for the belt 32 by the numerals 34a to 34d. As shown inFIG. 9 a hinged beam 35 supports the upper carriage assembly on amachine frame 37 so that the assembly can pivot about a horizontal axis36. The bottom carriage for the driving of the lower belt 32 issupported on the machine frame by a cantilevered beam 38. Thisarrangement enables both the casting belts 31 and 32 to be removed forrenewal from the ends of the beams 35 and 38, i.e. by movement to theright in FIG. 9.

The hinged beam 35 is connected to the machine frame 37 by ahydraulically controlled linkage 39 by which the upper belt 31 ismaintained at the correct level.

Molten casting material is supplied to the belts from a feeder 40 shownin FIGS. 7 and 8 which can be of conventional form. This part of theapparatus forms no part of the present invention and will not bedescribed in detail since its function will be familiar to those skilledin this art. Molten material fed by the feeder 40 is deposited betweenthe two belts 31 and 32. Cooling is provided for one or both of thebelts so that the material solidifies as the beltsmove and a solid strip41 emerges from between the belts. The precise manner in which the sidesofjthe strip areformed will be described but after the materialhas'solidified the individual anodes 10 are separated by shearingapparatus 44 again of conventional form.

In order to prevent the molten casting material from spilling over theedges of the lower belt 32 this lower belt is provided with edge dams 42only one ofwhich is shown in FIG. 7. The two edge dams 42, the lowerbelt 32 and the upper belt 31 together form a mould in which the moltenmaterial is cast and solidifies.

The form of the edge dams 42 will now be described.

Referring firstly to FIGS. 10 and 11 it will be seen that the edge damsare formed from numerous small metal blocks 50 which are connectedtogether in end-to-end relationship by means of a continuous flexiblemetal strip 51 shown in FIG. 11. Further detail will be given of themanner of connection of the metal blocks 50 to one another withreference to FIG. 12 onwards. The edge dams are not attached to thelower belt 32 but move with it on its upper run so as to provide a tightseal at the edge of the lower belt and so prevent the molten metal fromspilling.

As can clearly be seen from FIG. 7 the edge dams 42 are longer than thelower belt 32 and do not pass around the rollers 34a to 34d but hangdown in a loop below the lower belt. The path followed by the edge damswill be described in further detail below.

FIG. 10 shows the downstream end of the lower belt 32 as it passesaround the upper right-hand roller 34d. In order to form thelaterally-extending lugs 11 when manufacturing anodes of the types shownin FIGS. 1, 2, 3, 5 and 6, each of the edge dams is provided with anumber of recesses 53, one of which is shown in FIG. 10, so that thecasting material will fill the recesses and thus form laterallyextending lugs at positions spaced along the length of the cast strip.The strip can be cut into lengths with the lugs 11 at or near the top ofthe anodes by means of the shearing apparatus 44 shown in FIGS. 7 and 8.Whilst the lugs 11 can be made to ride out of the edge dam recesses 53merely by virtue of a downwardly-inclined section 54 of the edge dams asshown in FIG. 10, the process of removal of the strip from the mould isassisted by the fact that the trailing end wall 64 of each recess 53 forthe lugs 11 is inclined at an angle to the vertical. In the presentembodiment the angle of inclination is l4 /z. The leading end wall 65 ofeach recess 53 may also be inclined at a slight angle, for example 5 tothe vertical, although it is desirable that this inclination is not toolarge since, if it is too large, the lugs which are cast cannot be hungsatisfactorily in the refining tanks.

By virtue of the shallow angle of inclination of the edge darn section54 with respect to the horizontal path of the cast strip, and if desiredthe sloping of the trailing and leading faces-of the edge dam recesses,it is found that the lugs 11 formed on the anodes ride out of therecesses easily. The angle of inclination can vary according torequirements but may for example be between 2 and 10, and specificallyin the embodiment illustrated is approximately 5.

In FIG. 10 the strip is shown emerging from between the two castingbelts 31 and 32 and it is supported by rollers 55a and 55b after it haspassed beyond the position where the belt 32 passes towards the roller340. The roller 55b is mounted on a water-cooled shaft 56.

The lower casting belt 32 passes around the rollers 34d while the edgedams separate from the belt. Each edge dam passes through a guide 57.The guide is inclined at a slight angle to the horizontal in a downwarddirection so that the path tak'enby the edge dams is below that taken bythe cast strip. The guide 57 is shown in more detail in FIG. 11 andcomprises an upright 58 mounted on a cantilever arm 59 carried by themachine frame 37. A support bracket 61 is carried at the top of theupright 58 and the guide 57 is attached to the bracket 61. The rollers55a and 55b are also carried by the upright 58. The guide is ofsubstantially horizontal U-shape, one lower limb 62 being longer thanthe other upper limb 63, the longer limb being arranged to support theedge dam and the shorter limb passing over the top of the dam andserving merely to restrain the edge dam from movement upwards orlaterally of the support. As shown in FIG. 11, and as will be describedwith reference to FIGS. 12-17, the edge dam is formed in a number ofblocks 50 including replaceable faces 52 facing the casting region.

The guide defines the path for the inclined section 54 referred toabove, this section extending in a flat plane as far as the lower end ofthe upper limb 63 of the guide. Thereafter the lower limb 62, togetherwith the bracket 61 form a curved guide section 57A followed by afurther flat section 57B of the lower limb 62 which terminates with aninwardly turned flange 62A connected to the cantilever arm 59. The edgedams follow the path of the guide as far as the arm 59 and then loopfreely downwards as shown in FIG. 7, the return path being defined by afurther guide 88 positioned adjacent the rollers 34a and 34b.

Reference will now be made to FIGS. 12 and 13 which show part of an edgedam suitable for the manufacture of the form of anode shown in FIG. 2.Edge dam blocks of different shapes are employed but where the straightside edges of the anode are to be cast the individual blocks 50 are ofrectangular form. Blocks 50A and 50B together form between them a recess53 for the formation of a lug, whilst blocks 50C and 50D haveprojections 70 and 71 respectively which are shaped to form the anoderecesses 15.

The edge dam block 50A, which has the tapered wall 64 formed thereon,has this wall lying at an angle with respect to the further side 73 ofthe block so that the recess 53 is somewhat wedge-shaped in plan toproduce the form of lug referred to. The tapering of the lug has thebenefit that its weight is diminished and the flow of metal into and therelease of gas from the mould is improved.

The leading and trailing edges of the parts 70 and 71 respectively ofthe edge blocks 50C and 50D are angled at 29 and 28 respectively so asto permit the cast metal to be more easily removed from the dams. Theremainder of the specific construction of this edge dam will bedescribed shortly but firstly reference will be made to FIGS. 14 and 15,which show the form the edge dam takes if it is desired to cast an anodeof the type shown in FIG. 4. In this case, for each anode, each edge damis formed completely by rectangular blocks 50 except for one block 50Ewhich has an appropriate end part 75 for the formation of the recesses16. Since no lugs are to be formed in the case of the anodes of FIG. 4,the edge dam blocks have no recesses formed therein.

In both the construction of FIGS. 12 and 13 on the one hand and FIGS. 14and on the other hand, in

order to prevent the joints opening between the blocks, and fins formingon the anode, a stranded flexible cable 81 is used to supplement themetal strip 51 extending between the blocks as shown in FIGS. 11 and 12.The flexible cable binds the blocks together. The cable 8] may be about12 inches longer than the length of an anode and passes through holes82, shown in detail in FIGS. 11 and 15, from the downstream side of onerecess 53 to the upstream side of the next recess 53. The cable 81 istensioned and anchored in the blocks defining the upstream anddownstream edges of the recesses 53 by means of socket set screws 83 and84. The ends of the cable which protrude through the dams are then cutoff. If desired, in order to maintain substantially uniform tension inthe cable irrespective of temperature changes, the cable 81 may be intwo parts, each of about equal length and joined together by helicalspring. The spring need be no more than about threeeighths inch outsidediameter so that it could be housed in the holes 82 in the edge damblocks through which the cable 81 extends.

Additional recesses 85 (see FIG. 15) are provided in the blocks of boththe edge dams to enable the dams to be synchronised to ensure that thelugs and recesses on the anodes produced are symmetrical, or not, asdesired. This synchronisation can be achieved for example by providingat a shaft 114 across the width of the apparatus and carried in twosuitable bearings 115 and having keyed at its ends two wheels 116provided with teeth 117 of such shape and pitch that they would en gagewith the synchronising recesses 85. Provision can be made forlongitudinal adjustment of the wheels on their shaft so that thedistance between them could be adjusted to suit the position of the edgedams (by varying which the width of the cast strip itself is adjusted asdesired).

The edge dam synchronising recesses 85 also provide means forestablishing the position of a mould cavity (for example) when themachine is closed and in use. They would therefore facilitate theautomatic spraying of a release agent into the mould cavities prior tothese coming into the casting zone of the machine. Such sprays could,for example, be conveniently turned on and off at the appropriate timesby switches or cams actuated by the rotation of the shaft 114 carryingthe wheels 116 intermeshing with the recesses 85.

FIG. 16 and 17 show a somewhat modified edge dam which may be needed ifcertain circumstances arise. As the continuously cast strip solidifiesit will contract and the distance between the adjacent lugs on each sideof the cast strip will tend to become less than the distance between theadjacent recesses 53 in the edge dam in which the lugs are formed. Inthe majority of cases this will not create any difficulty since when onelug is at the point of disengagement from the recess 53 the adjacentupstream lug will either still be in the liquid metal phase or at leastin a plastic condition due to its high temperature. The lug and stripcan, therefore, extend by an amount sufficient to neutralise thecontraction of the downstream colder portion of the strip. However,there may be occasions when this does not happen, for example whencasting at a fast rate with metals which quickly solidfy and the lugsare so close together that the upstream lug is below solidifyingtemperature be fore the one immediately downstream of it has beendisengaged. In such a situation the modified edge dam of FIGS. 16 and 17can be used.

It will be seen that the edge dam block immediately upstream of theblock 90 is formed into two nonslightly oversized holes 97 in the block91a. The part I 91b has a projection 98 extending at right angles to itslongitudinal axis and which is able to slide over the end face 99 of theblock 91a.

When the split block is in the position shown in FIGS. 16 and 17, i.e.adjacent the block 90, the inner face 92 of the block 90 is extended soas to be substantially flush with the projection 98. An anode formedwith such an edge darn would be as shown in FIG. and would have an extrarecess 49 on each side adjacent its lower edge. This would have nofunctional disadvantage.

It is not necessary for the split block to be positioned adjacent theblock 90 and if it were positioned elsewhere the projection 98 couldterminate at the chaindotted line 100 shown in FIG. 16. The projection98 is sufficient to ensure that any flash on the sides of the strip dueto liquid metal penetrating between the edge dam and the casting beltswould not penetrate as far as the space 102 normally existing betweenthe two parts 91a and 91b. The distance by which the projection 98extends beyond the end face of the part 91a is normally about 10 mm.

In use the strip will contract and when this happens the blocks 90 and9lb will move towards the part 91a. Such movement will create a gapbetween the block 90 and its adjacent block 104 and will cause theprojection 98 to slide forward over the end face 99 of the block 910.The gap between the blocks 90 and 104 will have no consequence since themetal of this position has already solidified and the sliding of theprojection 98 over the block 91a will also have no consequence since thecontraction of the strip will have caused the recess in its edge to havemoved by substantially the same amount as the block 91b.

When the lugs have been disengaged from the edge dams the springs 93 and94 will close the gap between the blocks 90 and 104.

In all the embodiments described the edge dam blocks may be connected tothe flexible strip 51 by means of a screw or rivet, for example asindicated at 105 in FIG. 16. About one block in four could be sosecured. Inthe modified construction of FIGS. 16 and 17 it will ofcourse be ensured that none of the movable blocks will be so secured tothe strip 51.

FIG. 18 illustrates an alternative embodiment similar to FIG. 7 exceptthat the edge dams 110 are constrained to move above the cast strip 111over a number of rollers 113 and back, downwards over a guide 88A. Thestrip extends downwards at a shallow angle of approximately 5 to thehorizontal.

The blocks have been shown in FIGS. 11, 12 and 14 as having'separate endpieces 52 while those shown in FIGS. 16 and 17 are shown as being ofone-piece construction. Clearly all the blocks shown could haveremovable end-pieces although this is not essential and they could allbe of one-piece construction.

In general the blocks or end-pieces having one or more edges in contactwith the cast strip'should be made from a suitable grade of alloy steelor titanium.

If the edge is in the form of a removable piece fixed to a separateblock, the block may be made from a different material with suitableproperties, such as copper or a light metal alloy.

Various other modifications are possible, for example, the function ofthe guide 57 could'be performed by a series of small rollers rotating onaxles fixed to the guide support 58 so that they support and constrainthe blocks to follow substantially the same path as indicated on thedrawing.

The edge dams described could also be used in casting machines of thetype in which the travelling top and bottom faces of the strip mould areformed by a series of water cooled segmented blocks connected togetherby chain type elements to form a continuous sequence. An example of sucha machine is the Hunter-Douglas machine.

What we claim as our invention and desire to secure by Letters Patentis:

l. Molten metal casting apparatus comprising an endless supporting beltand movable edge dams defining between them and with the belt a castingregion for a continuously cast strip, the edge dams each having alaterally shouldered section to enable the integral formation ofasupporting shoulder on each side of the cast strip.

2. Apparatus for the continuous casting of a metal strip comprising atleast one substantially flat supporting belt which is movable, in acasting region, in a planar path, a pair of horizontally spaced edgedams engaging the 'casting region of the supporting belt anddefiningtherewith a casting channel, the dams being movable in the samedirection and at substantially the same speed as the supporting belt,the edge dams having opposed faces which at least at one region of eachhas a laterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast metal strip. I

3. Apparatus as claimed in claim 1 in which the laterally shoulderedsection comprises a recess in the edge dam.

4. Apparatus as claimed in claim 1 in which the laterally shoulderedsection comprises a projection from the remainder of the face of thedam.

5. Apparatus as claimed in claim 1 in which the I shouldered sectioncomprises a recess in, and an adjacent projection from the face of thedam whereby the casting is formed, in each edge face thereof, with alaterally projecting lug and an adjacent inwardly extending recess.

6. Apparatus as claimed in claim 1 including synchronisation meansadapted to cooperate with means on each edge dam to maintain theadvancement of the dams in correctly phased relationship.

7. Apparatus for the continuous casting of anodes in the form of a metalstrip including molten metal feed means, mould conveyor means, ,caststrip receiving means, and anode severing means in the region of thecast strip receiving means, the mould conveyor means comprising a pairof horizontal flexible conveyors each arranged to advance in a planardirection of travel, the conveyors being spaced one above the other todefine parallel top and bottom mould surfaces, lateral mould surfacesbeing defined by a pair of horizontally spaced edge dams each positionedbetween and engaging the mould surfaces of the flexible conveyors andbeing supported for movement therewith at substantially the same speed,the edge clams having opposed faces which, for each anode, has alaterally shouldered section to enable the integral formation of asupporting shoulder on each side of the anode.

8. Molten metal casting apparatus comprising an endless supporting beltand movable edge dams defining between them and with the belt a castingregion for a continuously cast strip, the edge dams each having alaterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast strip, means for supportingthe cast strip as it leaves the casting region, and means forconstraining the edge dams, beyond the casting region, to follow a pathwhich is inclined to the cast strip at a shallow vertical angle.

9. Apparatus as claimed in claim 8 in which the cast strip as it leavesthe casting region follows a substantially horizontal path, and themeans for constraining the edge dams causes the edge dams to movedownwardly beyond the casting region.

10. Apparatus as claimed in claim 8 in which the cast strip as it leavesthe casting region follows a downwardly inclined path and the means forconstraining the edge dams causes the edge dams to move upwardly beyondthe casting region.

11. Apparatus for the continuous casting of a metal strip comprising atleast one substantially flat supporting belt which is movable, in acasting region, in a planar path, a pair of horizontally spaced edgedams engaging the supporting belt in the casting region and definingtherewith a casting channel, the dams being movable in the samedirection and at substantially the same speed as the supporting belt,the edge dams having opposed faces which at least at one region of eachhas a laterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast metal strip, means forsupporting the cast strip as it leaves the casting region, and means forconstraining the edge dams, beyond the casting, to follow a path whichis inclined to the cast strip at a shallow vertical angle.

12. Apparatus as claimed in claim 11 in which the cast strip, as itleaves the casting region follows a substantially horizontal path, andthe edge dams are constrained to follow a downward path.

13. Apparatus as claimed in claim 11 wherein the angle of inclination ofthe edge dam path with respect to the cast strip is between 2 and 14.Apparatus as claimed in claim 13 wherein the angle of inclination is 5.

15. Apparatus for the continuous casting of anodes in the form of ametal strip including molten metal feed means, mould-forming conveyormeans, cast strip receiving means, and anode severing means in theregion of the cast strip receiving means, the mould conveyor meanscomprising a pair of horizontal flexible conveyors each arranged toadvance in a planar direction of travel, the conveyors being spaced oneabove the other to define parallel top and bottom mould surfaces,lateral mould surfaces being defined by a pair of horizontally spacededge dams each positioned between and engaging the mould surfaces of theflexible conveyors and being supported for movement therewith atsubstantially the same speed, the edge dams having opposed faces which,for each anode, have a laterally shouldered section to enable theintegral formation of a supporting shoulder on each side of the anode,and guide means for constraining the edge dams, beyond the castingregion to follow a path which is inclined at a shallow vertical angle tothe path of the cast strip in the region of the cast strip receivingmeans.

16. A method of continuously casting a metal strip comprising forming acasting region between an endless supporting belt and movable edge damswhich have laterally shouldered sections and introducing molten metalinto the casting region to form a cast strip having integral supportingshoulders defined by the laterally shouldered sections.

17. The method as claimed in claim 16 including guiding the cast stripalong a path which diverges at a shallow vertical angle from a sectionof path of the edge dams beyond the casting region.

18. The method as claimed in claim 16 wherein the laterally shoulderedsections comprise recesses in the edge dams and the molten metal flowsinto the recesses to form integral lugs on the strip.

19. A method of continuously casting anodes comprising forming a mouldbetween a pair of horizontal flexible conveyors each advancing in aplanar direction of travel and having lateral mould surfaces defined bya pair of horizontally spaced edge dams each positioned between andengaging the mould surfaces of the flexible conveyors and movingtherewith at substantially the same speed, the edge clams having opposedfaces which, for each anode, have laterally shouldered sections,introducing molten metal from feed means into the mould to form thereina cast strip having integral supporting shoulders defined by the saidlaterally shouldered sections and constraining the edge dams beyond thecasting region to follow a path which is inclined at a shallow verticalangle to the path of the cast strip leaving the mould, receiving thecast strip on cast receiving means, and severing the anodes from thestrip on the cast strip receiving means.

20. Molten metal casting apparatus comprising an endless supporting beltand movable edge dams defining between them and with the belt a castingregion for a continuously cast strip, said edge dams each having alaterally shouldered section to enable formation of a continuous supportshoulder on each side of the strip, said shouldered section including atrailing wall inclined to the vertical at a predetermined angle therebyto facilitate release of said strip from the edge dams.

21. The apparatus of claim 20 in which said shouldered portion comprisesa leading wall inclined to the vertical at a predetermined angle whichis less than the angle of inclination of said trailing wall.

1. Molten metal casting apparatus comprising an endless supporting beltand movable edge dams defining between them and with the belt a castingregion for a continuously cast strip, the edge dams each having alaterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast strip.
 2. Apparatus for thecontinuous casting of a metal strip comprising at least onesubstantially flat supporting belt which is movable, in a castingregion, in a planar path, a pair of horizontally spaced edge damsengaging the casting region of the supporting belt and definingtherewith a casting channel, the dams being movable in the samedirection and at substantially the same speed as the supporting belt,the edge dams having opposed faces which at least at one region of eachhas a laterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast metal strip.
 3. Apparatusas claimed in claim 1 in which the laterally shouldered sectioncomprises a recess in the edge dam.
 4. Apparatus as claimed in claim 1in which the laterally shouldered section comprises a projection fromthe remainder of the face of the dam.
 5. Apparatus as claimed in claim 1in which the shouldered section comprises a recess in, and an adjacentprojection from the face of the dam whereby the casting is formed, ineach edge face thereof, with a laterally projecting lug and an adjacentinwardly extending recess.
 6. Apparatus as claimed in claim 1 includingsynchronisation means adapted to cooperate with means on each edge damto maintain the advancement of the dams in correctly phasedrelationship.
 7. Apparatus for the continuous casting of anodes in theform of a metal strip including molten metal feed means, mould conveyormeans, cast strip receiving means, and anode severing means in theregion of the cast strip receiving means, the mould conveyor meanscomprIsing a pair of horizontal flexible conveyors each arranged toadvance in a planar direction of travel, the conveyors being spaced oneabove the other to define parallel top and bottom mould surfaces,lateral mould surfaces being defined by a pair of horizontally spacededge dams each positioned between and engaging the mould surfaces of theflexible conveyors and being supported for movement therewith atsubstantially the same speed, the edge dams having opposed faces which,for each anode, has a laterally shouldered section to enable theintegral formation of a supporting shoulder on each side of the anode.8. Molten metal casting apparatus comprising an endless supporting beltand movable edge dams defining between them and with the belt a castingregion for a continuously cast strip, the edge dams each having alaterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast strip, means for supportingthe cast strip as it leaves the casting region, and means forconstraining the edge dams, beyond the casting region, to follow a pathwhich is inclined to the cast strip at a shallow vertical angle. 9.Apparatus as claimed in claim 8 in which the cast strip as it leaves thecasting region follows a substantially horizontal path, and the meansfor constraining the edge dams causes the edge dams to move downwardlybeyond the casting region.
 10. Apparatus as claimed in claim 8 in whichthe cast strip as it leaves the casting region follows a downwardlyinclined path and the means for constraining the edge dams causes theedge dams to move upwardly beyond the casting region.
 11. Apparatus forthe continuous casting of a metal strip comprising at least onesubstantially flat supporting belt which is movable, in a castingregion, in a planar path, a pair of horizontally spaced edge damsengaging the supporting belt in the casting region and definingtherewith a casting channel, the dams being movable in the samedirection and at substantially the same speed as the supporting belt,the edge dams having opposed faces which at least at one region of eachhas a laterally shouldered section to enable the integral formation of asupporting shoulder on each side of the cast metal strip, means forsupporting the cast strip as it leaves the casting region, and means forconstraining the edge dams, beyond the casting, to follow a path whichis inclined to the cast strip at a shallow vertical angle.
 12. Apparatusas claimed in claim 11 in which the cast strip, as it leaves the castingregion follows a substantially horizontal path, and the edge dams areconstrained to follow a downward path.
 13. Apparatus as claimed in claim11 wherein the angle of inclination of the edge dam path with respect tothe cast strip is between 2* and 10*.
 14. Apparatus as claimed in claim13 wherein the angle of inclination is 5*.
 15. Apparatus for thecontinuous casting of anodes in the form of a metal strip includingmolten metal feed means, mould-forming conveyor means, cast stripreceiving means, and anode severing means in the region of the caststrip receiving means, the mould conveyor means comprising a pair ofhorizontal flexible conveyors each arranged to advance in a planardirection of travel, the conveyors being spaced one above the other todefine parallel top and bottom mould surfaces, lateral mould surfacesbeing defined by a pair of horizontally spaced edge dams each positionedbetween and engaging the mould surfaces of the flexible conveyors andbeing supported for movement therewith at substantially the same speed,the edge dams having opposed faces which, for each anode, have alaterally shouldered section to enable the integral formation of asupporting shoulder on each side of the anode, and guide means forconstraining the edge dams, beyond the casting region to follow a pathwhich is inclined at a shallow vertical angle to the path of the caststrip in the region of the cast strip receivinG means.
 16. A method ofcontinuously casting a metal strip comprising forming a casting regionbetween an endless supporting belt and movable edge dams which havelaterally shouldered sections and introducing molten metal into thecasting region to form a cast strip having integral supporting shouldersdefined by the laterally shouldered sections.
 17. The method as claimedin claim 16 including guiding the cast strip along a path which divergesat a shallow vertical angle from a section of path of the edge damsbeyond the casting region.
 18. The method as claimed in claim 16 whereinthe laterally shouldered sections comprise recesses in the edge dams andthe molten metal flows into the recesses to form integral lugs on thestrip.
 19. A method of continuously casting anodes comprising forming amould between a pair of horizontal flexible conveyors each advancing ina planar direction of travel and having lateral mould surfaces definedby a pair of horizontally spaced edge dams each positioned between andengaging the mould surfaces of the flexible conveyors and movingtherewith at substantially the same speed, the edge dams having opposedfaces which, for each anode, have laterally shouldered sections,introducing molten metal from feed means into the mould to form thereina cast strip having integral supporting shoulders defined by the saidlaterally shouldered sections and constraining the edge dams beyond thecasting region to follow a path which is inclined at a shallow verticalangle to the path of the cast strip leaving the mould, receiving thecast strip on cast receiving means, and severing the anodes from thestrip on the cast strip receiving means.
 20. Molten metal castingapparatus comprising an endless supporting belt and movable edge damsdefining between them and with the belt a casting region for acontinuously cast strip, said edge dams each having a laterallyshouldered section to enable formation of a continuous support shoulderon each side of the strip, said shouldered section including a trailingwall inclined to the vertical at a predetermined angle thereby tofacilitate release of said strip from the edge dams.
 21. The apparatusof claim 20 in which said shouldered portion comprises a leading wallinclined to the vertical at a predetermined angle which is less than theangle of inclination of said trailing wall.